Why are optical modules out of stock

High-speed 800G and 1.6T optical modules are currently in limited supply, with 1.6T modules particularly constrained due to upstream component shortages.Modules in Short SupplyThe optical module market is experiencing critical shortages in 1.6T modules, which are entering low-volume shipments and are constrained by limited production capacity and supply chain bottlenecks for key components such as EML chips, DSPs from Broadcom and Marvell, and foundry capacity . While 800G modules are in mass deployment, their supply is also tight due to surging demand from AI data centers and hyperscale cloud providers .Causes of ShortagesAI Infrastructure Demand: Generative AI clusters require significantly more fiber transceivers per GPU, driving exponential demand for high-speed optical modules .Upstream Component Constraints: Shortages of EML chips, DSPs, and silicon photonic components are limiting production of 1.6T modules .Transition to Next-Gen Technology: The shift from 400G to 800G and 1.6T modules is accelerating, creating temporary supply gaps as manufacturers scale production .Co-Packaged Optics (CPO) Adoption: New architectures like Nvidia's CPO roadmap are increasing demand for integrated 1.6T silicon photonics engines, further straining supply .Market Impact400G modules are expected to decline in shipment volume as hyperscalers upgrade to 800G and 1.6T solutions .1.6T modules remain in initial production, with shipments below one million units in 2025, making them the most constrained segment .Companies with strong vertical integration, such as Coherent and Lumentum, are better positioned to meet demand, while smaller firms face existential risks due to supply chain limitations .Recommendations for BuyersPlan orders well in advance, especially for 1.6T modules, as lead times are extended and supply is limited .Establish supplier relationships proactively for optical transceivers, silicon photonic chips, DSP chips, and fiber connectors to mitigate shortages .Monitor market trends for 800G and 1.6T modules, as these segments are driving the next wave of AI infrastructure upgrades . In summary, 1.6T optical modules are the most constrained, followed by high-demand 800G modules, with shortages driven by AI infrastructure expansion, upstream component scarcity, and rapid adoption of next-generation optical technologies .